JP3441250B2 - Underwater mixer - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a submersible mixer used for stirring stored sewage in a sewage tank, a reservoir or the like.

[0002]

2. Description of the Related Art An underwater mixer used for stirring sewage or the like stored in a sewage tank usually has a motor and an impeller rotated by the motor. In the motor, a rotary shaft that is inserted through the shaft center rotates, and an impeller is attached to the tip of the rotary shaft.

FIG. 3 shows an example of a mounting structure of a rotary shaft and an impeller of a submersible mixer. The rotating shaft 41 is inserted through an axial center portion of an oil casing 42 attached to the motor, and a tip end portion of the rotating shaft 41 is attached to the oil casing 42.
It is located within the tip of the. The impeller 50 has a rotating shaft 41.
And a plurality of stirring blades 52 attached to the periphery of the hub 51.

The hub 51 is located outside the oil casing 42, and has a cylindrical main body portion 51a to which the base end portions of the respective stirring blades 52 are attached, and an outer diameter smaller than the main body portion 51a, and the tip end of the oil casing 42. A connecting portion 51b protruding from the main body portion 51a so as to be fitted inside the connecting portion, and a connecting portion 5
It has a cylindrical boss portion 51c which is provided so as to further project from the oil casing 1b into the oil casing 42 and is fitted into the tip end portion of the rotating shaft 41.

The tip of the rotary shaft 41 is the boss portion 5 of the hub 51.
It is fitted in 1c, and its tip end surface is located in the connecting portion 51b of the hub 51. A pressing member 53 is attached to the tip end surface of the rotary shaft 41 with a bolt 54. The pressing member 53 is in pressure contact with a step 51e provided on the inner peripheral surface of the connecting portion 51b. As a result, the rotary shaft 41 and the hub 51 are integrally attached, and both rotate together.

The connecting portion 51b is concentrically arranged at the tip of the oil casing 42, and the oil casing 4
A seal ring 51d is fitted between the tip of the second member and the connecting portion 51b of the hub 51. This seal ring 51
d holds the hub 51, which rotates integrally with the rotating shaft 41, concentrically with the tip of the oil casing 42.

A gap is formed along the axial direction between the connecting portion 51b of the hub 51 extending outward from the oil casing 42 and the tip of the oil casing 42.

The submersible mixer having such a structure is installed, for example, at the bottom of a sewage tank, and when the impeller 50 is rotated by rotating the rotating shaft 41, as shown by an arrow B in FIG. , Generates a water flow in the direction along the rotation axis 41. Thereby, the sewage in the sewage tank is stirred.

[0009]

Foreign matter such as hair is mixed in the sewage, and the foreign matter flows with the water flow generated by the rotation of the impeller 50. Since the water flow flows along the oil casing 42, if a gap is formed along the axial direction between the tip end surface of the oil casing 42 and the intermediate portion 51b of the hub 51, the water flow will fall within the gap. Easily penetrate into. As a result, foreign matter such as hair mixed in the water stream may enter the gap and become entangled with the hub 51. When foreign matter such as hair is entangled with the hub 51, a large load is applied to the hub 51, and the motor may be overloaded.

The present invention solves such a problem, and an object thereof is a submersible mixer which can be stably driven for a long time without the possibility that foreign matter such as hair is entangled with the hub of the impeller. To provide.

[0011]

According to the present invention, there is provided a motor in which a tip end of a rotary shaft which is inserted into an axial center portion of a casing and is rotatably supported by the casing is positioned in the tip end portion of the casing. A hub attached to the tip of the rotating shaft and extending from the casing, and a plurality of stirring blades attached around the hub extending from the casing to generate a water flow along the rotating shaft with the casing upstream. An impeller having an impeller having a hub, the impeller hub being held concentrically in the casing of the motor through a seal ring, and an overlap ring having an overlap portion covering the hub extending from the casing over the entire circumference. Is provided in a fitted state at the tip of the casing.

The hub extending from the casing is provided with a fitting ring in a fitted state which is covered with a predetermined gap in the radial direction from the overlapping portion of the overlapping ring.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a vertical cross-sectional view of the submersible mixer of the present invention, and FIG. 2 is an enlarged cross-sectional view of the essential part thereof. This submersible mixer is installed and used at the bottom of a sewer tank or the like, and has a motor 10 and an impeller 30 that is rotationally driven by the motor 10.

The motor 10 includes a cylindrical stator casing 11 having an axial center in a horizontal state, and a stator 1
2 is attached, and the rotor 13 is rotatably arranged in the stator 12. And rotor 1
The rotary shaft 14 is inserted through the shaft center portion of 3.

One end of the stator casing 11 is covered with a motor cover 15, and the motor cover 15 accommodates electric parts and the like. A slider 16 is attached to the motor cover 15, and the slider 16 allows the entire submersible mixer to be installed on the bottom of a sewer tank or the like. The submersible mixer installed in the lower part of the sewage tank or the like is held in a horizontal state by the chain 19 attached to the stator casing 11.

The other end of the stator casing 11 is covered with a bearing bracket 17, and the rotary shaft 14 is inserted through the shaft center portion of the bearing bracket 17. The rotary shaft 14 is rotatably supported by a bearing 18 attached to a bearing bracket 17.

The rotary shaft 1 through which the bearing bracket 17 is inserted.
The end of No. 4 is covered with an oil casing 21 attached to the bearing bracket 17. The oil casing 21 is in the shape of a hollow truncated cone whose outer diameter is gradually reduced as the distance from the stator casing 11 increases, and the partition wall 21a whose interior is vertical makes the oil chamber 21b and the fitting chamber 21c on the front end side. And is divided into two in the axial direction. The rotary shaft 14 penetrating the partition wall 21 a is inserted through the axial center of the oil casing 21, and the tip end of the rotary shaft 14 is inserted through the fitting chamber 21 c of the oil casing 21. The rotating shaft 14 located in the oil chamber 21b includes a bearing bracket 17 and a partition wall portion 2.
A mechanical seal 22 supported between 1a and 1a is fitted. Oil chamber 21 around the mechanical seal 22
Sealing oil is filled in b.

The tip portion of the rotary shaft 14 which is inserted through the fitting chamber 21c of the oil casing 21 has an oil casing 21
It is located in a support portion 21d provided at the tip of the.
The support portion 21d has a cylindrical shape with a constant inner diameter and outer diameter, and the impeller 30 is attached to the tip end portion of the rotating shaft 14 arranged concentrically inside the support portion 21d.
The impeller 30 has a cylindrical hub 31 attached to the tip of the rotary shaft 14 and a plurality of stirring blades 32 attached to the outer peripheral surface of the hub 31.

The hub 31 is located outside the oil casing 21 and has a cylindrical main body 31a to which the base end portions of the respective stirring blades 32 are attached, and an outer diameter smaller than the main body 31a to support the oil casing 21. The connecting portion 31b protruding from the main body portion 31a so as to be fitted to the portion 21d, and the fitting chamber 21 of the oil casing 21 from the connecting portion 31b.
It has a cylindrical boss portion 31c which is provided so as to project into c and is fitted into the tip end portion of the rotary shaft 14.

A boss portion 3 fitted to the tip of the rotary shaft 14.
1c has a tapered shape in which the outer diameter is gradually increased as the outer peripheral surface of the base end portion is closer to the connecting portion 31b. The tip end of the rotary shaft 14 is fitted in the boss portion 31c in the hub 31, and the tip end surface is located in the connecting portion 31b of the hub 31. The pressing member 33 is attached to the tip end surface of the rotary shaft 14 with a bolt 34.
The pressing member 33 is pressed against a step 31e provided on the inner peripheral surface of the connecting portion 31b, whereby the rotary shaft 1
4 and the hub 31 are mounted so that they can rotate integrally.

The connecting portion 31b is concentrically arranged in a cylindrical supporting portion 21d provided at the tip of the oil casing 21, and supports 21d of the oil casing 21.
A ring-shaped seal ring 31d is fitted between the hub and the connecting portion 31b of the hub 31. This seal ring 31d
The hub 31 that is fitted to the rotating shaft 14 and rotates integrally with the rotating shaft 14 is attached to the support portion 2 of the oil casing 21.
Hold concentric with 1d.

The connecting portion 3 of the body portion 31a of the hub 31
A groove 31f is formed on the outer peripheral portion of the end portion adjacent to 1b. The concave groove 31f is open to the outer peripheral side of the main body 31a and the end face side in contact with the connecting portion 31b, and is provided over the entire circumference of the main body 31a. Groove 31f
Is in a state of being close to the base end portion of the stirring blade 32, and an annular fitting ring 35 is fitted therein. The fitting ring 35 is made of, for example, stainless steel, and its outer peripheral surface is substantially flush with the outer peripheral surface of the main body portion 31 a of the hub 31. A concave portion 35a that is open toward the outer peripheral side and the stirring blade 32 side is provided on the outer peripheral portion of the end portion of the fitting ring 35 on the stirring blade 32 side over the entire circumference.

Support part 21 in oil casing 21
The outer peripheral portion of d is also provided with a concave groove 21e that is open toward the outer peripheral side and the front end surface side, and a cylindrical overlap ring 24 is provided in the concave groove 21e. The overlap ring 24 is made of, for example, stainless steel, and has an overlap portion 24a that projects toward the tip side of the support portion 21d of the oil casing 21. This overlapping portion 24a is
The fitting ring 35 is inserted through the outer side of the fitting ring 35 with a slight gap left between the fitting ring 35 and the fitting ring 35 as a whole.

As shown in FIG. 1, each agitating blade 32 of the impeller 30 is located inside a draft ring 37 having open end surfaces. The draft ring 37 is supported concentrically with the impeller 30 by a support member 26 attached to an arm portion 25 extending downward from the oil casing 21.

The submersible mixer having such a structure is installed, for example, at the bottom of the sewage tank and is used for stirring the sewage stored in the sewage tank. When the motor 10 of the submersible mixer is driven and the rotary shaft 14 is rotated,
Impeller 3 integrally attached to the tip of the rotary shaft 14.
0 rotates, and sewage flows in the horizontal direction along the stator casing 11 and the oil casing 21 as indicated by arrow A in FIG. Thereby, the sewage in the sewage tank is agitated.

In the submersible mixer of the present invention, the gap between the oil casing 21 and the hub 31 of the impeller 30 is covered by the overlap portion 24a of the overlap ring 24, and therefore the overlap portion 24a and the fitting ring. Since a radial gap is formed between the overlap portion 24a and the fitting ring 35,
The sewage flowing in the direction opposite to the flow direction of the sewage will enter the gap between the sewage and the sewage. Moreover, since the gap between the overlapping portion 24a and the fitting ring 35 communicates with the gap between the connecting portion 31b of the hub 31 and the tip end surface of the oil casing 21 along the axial direction in an orthogonal state, It is not easy for the sewage that has entered the gap between the overlapping portion 24a and the fitting ring 35 to enter the gap along the axial direction, and the amount of sewage that enters the gap is significantly reduced. It As a result, there is no risk that foreign matter such as hair mixed in the sewage will enter the gap between the overlapping portion 24a and the fitting ring 35, and the foreign matter such as hair does not enter the oil casing 21 and the impeller 30. Hub 3
There is no possibility that the motor 10 is overloaded by being entangled in the gap with the motor 1.

The overlap portion 24a of the overlap ring 24 has a groove 3 in the main body 31a of the hub 31.
Since the fitting ring 35 fitted to 1f forms a constant gap, there is no possibility that the fitting ring 35 will come into contact with the overlapping portion 24a due to the vibration caused by the rotation of the hub 31. Therefore, the fitting ring 35
Further, the overlapping ring 24 has a long life, and the submersible mixer operates stably for a long period of time.

Further, since the fitting ring 35 is in a state of being fitted to the hub 31, the fitting ring 35 does not move the hub 31 to the rotary shaft 14.
It can be easily replaced by removing it from.

[0030]

As described above, the submersible mixer of the present invention is
Since the gap between the tip surface of the casing and the facing part of the hub of the impeller is covered by the overlap part of the overlap ring fitted to the tip part of the casing, it is mixed in the water flow. Foreign matter such as hair
There is no risk of entering the gap and becoming entangled with the hub. Therefore, there is no risk of overloading the motor, and sewage and the like in the sewage tank can be stably stirred for a long period of time.

Further, since the overlapping portion of the overlapping ring has a constant gap with respect to the fitting ring fitted to the hub, even if the hub vibrates due to rotation of the impeller, the overlapping ring is There is no danger of contacting the overlapping part of the and the durability is significantly improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an example of a submersible mixer of the present invention.

FIG. 2 is an enlarged sectional view of a main part of the submersible mixer.

FIG. 3 is an enlarged sectional view of a main part of a conventional submersible mixer.

[Explanation of symbols]

10 motors 11 Stator casing 12 Stator 13 rotor 14 rotation axis 21 Oil casing 21d support 21e concave groove 22 Mechanical seal 24 Overlap ring 24a Overlap part 30 impeller 31 Hub 31a main body 31b connection part 31c Boss 31d seal ring 31f concave groove 32 stirring blades 35 Mating ring 35a recess

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliography Sho 61-162594 (JP, U) Rikai Hei 3-17200 (JP, U) Rikai 58-96088 (JP, U) Rikai Sho 61- 140197 (JP, U) S. 62-42211 (JP, Y1) (58) Fields investigated (Int.Cl. ⁷ , DB name) F04D 1/00-29/70 B01F 5 / 00,7 / 00

Claims (2)

(57) [Claims] 1. When it is inserted into a shaft center portion of a casing,
The tip of the rotating shaft that is rotatably supported by the casing.
And Motoru but which is located within the distal end of the casing, rotary
A hook attached to the tip of the shaft and extending from the casing.
And around the hub that extends from the casing.
Attached along the axis of rotation with the casing upstream
An impeller having a plurality of stirring blades for generating water flow , or
The impeller hub is sealed to the motor casing.
It is held concentrically through the ring and the casing
The casing has an overlapping ring that has an overlapping part that covers the entire hub of the hub.
An underwater mixer characterized in that it is provided in a fitted state at the end . 2. The hub extending from the casing includes:
The overlapping part of the overlap ring is the radial direction
Water mixer according to claim 1, fitting ring covered with a predetermined gap is provided in a fitting state.